Control device for parenteral liquid feed apparatus

ABSTRACT

A fluid flow control device for an administration set used to introduce parenteral liquids into a patient. The control device has a body releasably attached to a container storing the liquid and connected to a feeding tube for carrying the liquid to a hypodermic needle. A cone-shaped valve connected to a float controls the rate of flow of liquid through a passageway in the body. The valve and float are movably mounted on the body. When the level of liquid in the container is lowered to or reaches a point where the container is substantially empty, an amount of liquid is retained in the container so that limited flow of liquid through the passageway is continued for a period of time.

PAIENIEB 1 3973 3,738.36 1

INVENTOR. MAYNARD L. PRICE Z BMJW ATTORNEYS CONTROL DEVICE FORPARENTERAL LIQUID FEED APPARATUS BACKGROUND OF INVENTION Intravenousliquids are administered by gravity feed from an elevated and invertedcontainer storing the liquid. The liquid is delivered from the containerinto a vein of a patient through a feed tube coupled to a hypodermicneedle. Check valve devices have been developed to stop administrationof the parenteral liquid when the liquid is nearly exhausted. Theseunits are designed to abruptly stop the flow of fluid to prevent thedanger of air or other gases being passed from the unit to the patient.Martinez discloses in U. S. Pat. No. 2,784,733 a float-type check valveoperative to stop the flow of fluid in an administration set. A similartype valve is disclosed by Bernstein in U. S. Pat. No. 3,227,l73. Othertypes of valves, as flexible diaphrams have been employed to close offor seal the outlet opening of an apparatus for administering aparenteral solution. An example of this diaphram-type valve is shown inU. S. Pat. No. 3,216,419. When the valve structures in all of theseintravenous devices are closed, the fluid flow is terminated.

SUMMARY OF INVENTION The invention is directed to a fluid flow controldevice for an administration set for parenteral liquids. The device isoperable to reduce the rate of flow of liquid in conjunction with thelevel of liquid in the container attached to the administration set. Thecontrol device has a body in the form of a cap that is attached to theoutlet portion of the container. The body has an outlet passageway fordirecting a liquid to a collector member connected to a tube carryingthe hypodermic needle. Liquid control means is movably mounted on thebody for controlling the rate of flow of liquid through the passagewaywhen the level of liquid in the container approaches the body. Thecontrol means has a movable valve that is insertable into the passagewaywhich restricts the flow of liquid through the passageway at a reducedrate. For example, the flow rate can be reduced to four or five dropsper minute. This flow rate allows the intravenous opening in thehypodermic needle to remain open for a period of time. This period oftime is sufficient for the attendants to change the container before theliquid runs out. The position of the valve is controlled with a floatlocated in the bottom portion of the container. The body has a supportslidably supporting a connecting rod secured to the float and the valve.

An object of the invention is to provide a parenteral liquid feedcontrol device that will automatically reduce the flow rate ofintravenous liquid flowing through the tube connected to the hypodermicneedle when the level of liquid in the container approaches the bottomof the container. A further object of the invention is to provide aliquid feed control device that is a one-piece assembled unit which isattachable to the conventional container storing the liquid.

IN THE DRAWING FIG. 1 is an elevational view of an intravenous liquidfeeding apparatus having the liquid feed control device of theinvention;

the liquid to a patient. The apparatus 10 is secured to the neck or openend of a bottle or container 11 storing the intravenous fluid 12 beingadministered to the patient. The lower end of the apparatus includes anelongated, flexible feed tube 13 of rubber, plastic, or the like. Thefeed tube 13 is connected to a hollow hypodermic needle 14. The needle14 has its forward portion inserted into the arm 16 of the patient. Apinch valve 17, or similar control valve, carried by the tube 13,controls the flow rate of liquid through the tube. The pinch valve 17may be replaced by flow meters measuring the rate of intravenousinfusion of the parenteral liquid. Examples of suitable flow meters areshown in U. S. Pat. Nos. 3,348,543 and 3,587,3l3.

In use, the container 11 is replaced when the supply of fluid in thecontainer 11 has been exhausted. Prior to the present invention, thegravity-type intravenous administrators were provided with check valveswhich terminated the infusion to eliminate admission of air into thefeed tube. When the flow of intravenous fluid is terminated, the needlebecomes clogged. A new needle is needed to continue the feeding ofsubsequent amounts of liquid. Replacing the container and needlerequires additional time and subjects the patient to additional pain.

As shown in FIG. 2, the container 11 has an open neck or end 18 havingexternal threads. The neck 18 surrounds the outlet passageway 19 of thecontainer 11. The liquid feeding apparatus 10 has a generally cup-shapedbody, indicated at 21, that is releasably mounted on the open end of thecontainer 11. The body 21 has an annular flange 22 provided withinternal threads that cooperate with the external threads on the neck 18so that the body is threaded onto the end of the container. A generallyflat wall 23, integral with flange 22, closes the container passageway19. The wall 23 has an outwardly directed boss or projection 24 havingan opening carrying a hollow cylindrical member or tube 26. The tube 26has a longitudinal outlet passage 27 for carrying liquid from thecontainer through body 21.

An elongated, cylindrical member 28 having a chamber 29 for collectingthe fluid discharged through the passageway 27 is attached to the boss24. The member 28 is transparent material, as glass or plastic, and hasa cylindrical upper end that is located in a tight sealed relationshipwith the external face, or surface, of the boss 24. The bottom of themember 28 has an outwardly directed nipple 30 having an outletpassageway 31. The feed tube 13 is mounted on the nipple 30 so that theliquid flows from chamber 29 through the passage 31 into the feed tube13.

The rate of flow of liquid 12 from the container 11 into the cylindricalmember 28 is controlled with a fluid control means indicated generallyat 32. Control means 32 has a valve 33 connected to a float 34 orsimilar buoyant memberwith a linear rod 36. The valve 33 has a generallycone shape with a smooth, downwardly and inwardly tapered circular outersurface 37. The lower end 38A of the valve 33 has a generally flatcircular shape and a diameter approximately one-half the diameter of theupper end 388 of the valve 33. The longitudinal length of the valve 33is approximately twice the diameter of the upper end 388. The insidediameter 39 of the tube 26 is slightly larger than the diameter of theupper end 38B of the valve 33.

As shown in FIG. 4, as the valve 33 moves into the passageway 27, thereis a continuous annular space 40 between the outer surface 37 of thevalve and the inside wall of the tube 26. This space 40 permitsrestricted flow of fluid through the passageway 27 during the closing ofthe valve 33. As shown in FIG. 2, as the fluid level in container 11approaches the body 21, the float 34 lowers the valve 33 into thepassageway 27. This restricts the flow of fluid through the passageway27. The annular space 40, being relatively small, permits the continuedflow of liquid at a reduced rate of, for example, approximately four orfive drops per minute. Other flow rates can be used to achieve limitedflow through needle 14. This allows the intravenous opening in thehypodermic needle to remain open for approximately 30-45 minutes. Thistime interval provides nurses or other personnel sufficient time tochange the container 11 before all the fluid is dispensed. Theadvantages of this type of operation are that it saves considerable timein administration of intravenous fluids and eliminates the necessity ofchanging needles.

The valve 33 is aligned with passageway 27 with a support 41 having alaterally directed portion or extension 42 spaced from and extended overthe passageway 27. The extension 42 has a longitudinal hole43 forslidably receiving the rod 36. This support 41 is secured to the insideface or surface of the wall 23 of the body 21. The body 21, support 41and extension 42 can be a one-piece member of metal, plastic, or similarmaterial. The valve 33 is located on the lower side of extension 42. Thefloat 34 is located on the upper side of extension 42 and extends intothe lower portion of the container 11. As shown in broken lines, whenthe level of liquid in the container is high, the float 34 holds thevalve 33 in engagement with the lower side of the extension 42. When thevalve 33 is in this position, the passageway 27 is entirely open,permitting the free flow of fluid from the container 11 through thepassageway 27 and into the chamber of the cylindrical member 28.

The body 21 carries an air check valve assembly indicated generally at44. Check valve assembly 44 has a cylindrical member 46 that is threadedinto a suitable hole in the wall 23. The member 46 has a passageway 47leading to a chamber 48 open to the inside of the body 21. A check valvein the form of a ball 49 is located in the chamber 48. A pin 51, orsimilar retaining structure, is used to hold the ball 49 in floatingassembled relation with the member 46. The ball 49 blocks the opening tothe passageway 47 so that the liquid 12 does not flow through the checkvalve. Reduced pressure in the container 11, caused by lowering thelevel of liquid in the container, will cause air to move into passageway47 to displace the ball, thereby allowing air into the container. Othertypes of one-way check valve assemblies can be used to permit air toreplace the dispensed fluid in container 11.

In operation, with the container 11 in an inverted gravity feedposition, as shown in FIGS. 1 and 2, the liq uid. 12 will exert liftingor buoyant forces on the float 34, thereby holding the valve 33 inengagement with the extension 42 and keeping the passageway 27 open. Theliquid 12 flows through the passageway 27 into the chamber 2?. The feedline 13 delivers the liquid to the hypodermic needle 14 which dischargesthe solution to the vein of the patient. As the level of the liquid inthe container 11 approaches the neck of the container, the

flow control apparatus 10 functions to reduce the flowrate of liquiddispensed from the container. The float 34 moves down with the levelofliquid, thereby moving the valve 33 downwardly into the passageway 27.The shaft 36, being linearly guided in the hole 43, directs the valveinto the upper end ofthe tube 26. The valve 33, having a continuouscone-shaped surface, restricts the rate of flow of liquid throughpassageway 27. The valve 33, being smaller than the passageway 27, doesnot at anytime stop or block the flow of liquid. The flow is reduced sothat it continues at a rate of, for example, approximately four or fivedrops per minute. Other reduced flow rates can be used to maintainlimited feeding of liquid to the needle 14. This will continuouslysupply liquid to the feeding tube so that the hypodermic needle willremain open. The slow rate of feed will insure that no air or othergases are allowed to enter the feed line 13. Also, the reduced flow rateof liquid provides the attending personnel sufficient time to remove thecontrol device from the substantially empty container and place it on afull container so that the feeding of the fluid to the patient can becontinued without the necessity of replacing the needle.

The invention has been described with respect to the preferredembodimenLlt is understood that various changes in size and material arewithin the purview of the invention as defined in the appended claims.

The embodiments of the invention in which an exclusive property orprivilege are claimed are defined as follows:

l. A parenteral liquid feed control device connectable to ,a containerfor storing parenteral liquid and a tube means to deliver the liquid toa needle comprising:

body means mountable on the container to receive parenteral liquid, saidbody means having an outlet passageway forsaid liquid; means connectedto the body means and adapted to be connected to the tube means to carrysaid liquid from the outlet passageway of the body means to the tubemeans; and liquid control means movably mounted on said body means forcontrollingthe rate of flow of liquid through the passageway, saidcontrol means having a valve member movable toward the passageway toallow limited flow of liquid through said passageway when the level ofthe liquid in the container reaches a point whereby an amount of liquidis retained in the container so that the limited flow of liquid throughsaid passageway is continued for a period of time, said valve memberbeing of a size smaller than said passageway whereby a limited amount offluid continues to flow through the passageway when the valve member islocated in said passageway.

2. The liquid feed control device of claim 1 wherein: said body meansincludes a cup-shaped member releasably attachable to the container.

3. The liquid feed control device of claim 1 wherein: said meansconnecting the body means to the tube means comprises an elongatedcylindrical member having a chamber for accumulating liquid.

4. The liquid feed control device of claim 3 wherein: said body meanshas an outwardly directed boss, said elongated hollow cylindrical memberhaving an end mounted on said boss.

5. The liquid feed control device of claim 1 wherein: said liquidcontrol means includes a float positionable in said container when thebody means is attached to the container, and means movably mounted onthe body means connecting the float to the valve member.

6. The liquid feed control device of claim 1 wherein: said valve memberhas a cone-shaped outer surface that is smaller than said passageway,whereby fluid continues to flow through said passageway when the valvemember is located in the passageway.

7. The liquid feed control device of claim 1 wherein: said body meanshas a support member projected toward the container, said support memberhaving a portion spaced from and extended over said passageway, saidliquid control means including a float located adjacent the containerside of the portion of the support, said valve being located adjacentthe opposite side of said body means has an outwardly directed boss,said means connecting the body means to the tube means comprising anelongated hollow cylindrical member having an end mounted on said boss.

10. The liquid feed control device of claim 7 including: an air checkvalve assembly mounted on said body means operable to permit air to flowinto the container to replace the liquid drained from the container.

1. A parenteral liquid feed control device connectable to a containerfor storing parenteral liquid and a tube means to deliver the liquid toa needle comprising: body means mountable on the container to receiveparenteral liquid, said body means having an outlet passageway for saidliquid; means connected to the body means and adapted to be connected tothe tube means to carry said liquid from the outlet passageway of thebody means to the tube means; and liquid control means movably mountedon said body means for controlling the rate of flow of liquid throughthe passageway, said control means having a valve member movable towardthe passageway to allow limited flow of liquid through said passagewaywhen the level of the liquid in the container reaches a point whereby anamount of liquid is retained in the container so that the limited flowof liquid through said passageway is continued for a period of time,said valve member being of a size smaller than said passageway whereby alimited amount of fluid continues to flow through the passageway whenthe valve member is located in said passageway.
 2. The liquid feedcontrol device of claim 1 wherein: said body means includes a cup-shapedmember releasably attachable to the container.
 3. The liquid feedcontrol device of claim 1 wherein: said means connecting the body meansto the tube means comprises an elongated cylindrical member having achamber for accumulating liquid.
 4. The liquid feed control device ofclaim 3 wherein: said body means has an outwardly directed boss, saidelongated hollow cylindrical member having an end mounted on said boss.5. The liquid feed control device of claim 1 wherein: said liquidcontrol means includes a float positionable in said container when thebody means is attached to the container, and means movably mounted onthe body means connecting the float to the valve member.
 6. The liquidfeed control device of claim 1 wherein: said valve member has acone-shaped outer surface that is smaller than said passageway, wherebyfluid continues to flow through said passageway when the valve member islocated in the passageway.
 7. The liquid feed control device of claim 1wherein: said body means has a support member projected toward thecontainer, said support member having a portion spaced from and extendedoVer said passageway, said liquid control means including a floatlocated adjacent the container side of the portion of the support, saidvalve being located adjacent the opposite side of said support, linearrod means slideably positioned in a hole in said portion of the supportconnected to the float and the valve member to linearly align the valvemember with the passageway.
 8. The liquid feed control device of claim 7wherein: said valve member has a downwardly converging cone-shaped outersurface and a transverse cross sectional area smaller than thetransverse cross sectional area of the passageway whereby fluidcontinues to flow through said passageway when the valve member islocated in the passageway.
 9. The liquid feed control device of claim 7wherein: said body means has an outwardly directed boss, said meansconnecting the body means to the tube means comprising an elongatedhollow cylindrical member having an end mounted on said boss.
 10. Theliquid feed control device of claim 7 including: an air check valveassembly mounted on said body means operable to permit air to flow intothe container to replace the liquid drained from the container.